Answer:
10 kph
Step-by-step explanation:
Find the speed of the current of the river.
20/(20 - c) + 180/(20 + c) = 8
20(20 + c) + 180(20 - c) = 8(400 - c^2)
8c^2 - 160c + 800 = 0
8(c^2 - 20c + 100) = 0
8(c - 10)^2 = 0
c = 10
The speed of the current of the river is 10 km/hour.
So let's say he was earring x before his raise. That means that:
x times 1.09 = 654 (1.09 represents 100% (this is the 1.0) of his original salary plus 9% (this is the .09) his raise.
So,
1.09x = 654; now divide both sides by 1.09 to isolate and solve for x, and you get x = $600.
Attention:THIS IS PART B <em>ONLY!</em>
First,find the unit rate.
35/2 and <em>x</em>/1
35 divided by 2 = 17.5 so the unit rate for J.K. is 17.5 pages per hour.
now,R.L.
45/3 and <em>x</em>/1
45 divided by 3 = 15 so the unit rate for R.L. is 15 pages per hour
now we need to divide 355 by 17.5 and divide it by 15.Whichever quotient is smaller,finishes the book first
355 divided by 17.5 = about 20 hrs----J.K.
355 divided by 15 = about 24 hrs-----R.L.
So,who read faster?
Answer:
7n-25 < -39
Step-by-step explanation: